The present invention relates to a method like that described in German Patent Application 196 45 769 (non-published). According to that method, a remote control is allocated to a base station arranged in a motor vehicle by having the base station transmit a search signal, whereupon any remote controls within the field of range of the search signal respond by sending back a contact signal at times characteristic of the remote controls. By analyzing the receipt times of the contact signal acknowledgments, the base station determines which remote controls are present. It selects one of them to perform a challenge/response verification with it. Since the information about which remote controls are present is not contained in the contact signal but in the time of its return, the contact signal may have a simple structure, and thus the entire identification can take place very rapidly. The identification speed is determined only by the number of time windows made available for the individual remote controls. However, if a base station is to be allocated a very large number of remote controls, this method loses its advantage of being fast.
An object of the present invention is to provide a method and a device suitable for carrying it out, permitting an allocation of a large number of remote controls to one base station and performing the allocation rapidly.
The method according to the present invention makes it possible to allocate a large number of remote controls to one base station with no change in the high allocation identification speed by allocating multiple remote controls to individual time slots. The number of time slots may be kept low, and the allocation identification speed may be kept high. An additional control signal with which the base station prompts the remote controls to transmit their device codes is advantageously used to differentiate multiple remote controls responding in the same time slot. The base station uses the interpretability of the device codes sent back as identification information. To select a certain remote control, the remote controls are induced to deliver random contact signals, with the first remote control responding unambiguously being selected. Therefore, the unambiguous identification of a remote control is made rapidly with only a few steps even when there are multiple remote controls assigned to the same time slot within the range of the base station.